1. Field of the Invention
The present invention relates to an improved method of and system for transferring data over a wireless communications network. More particularly, the present invention relates to an improved method of and system for transferring data from the Internet to wireless devices.
2. Description of the Prior Art
The Internet is a global computer network which comprises a vast number of computers and computer networks interconnected through communication links. The interconnected computers exchange information using various services, such as electronic mail and the World-Wide-Web (hereinafter, the “WWW”).
The present invention relates particularly to the WWW portion of the Internet. The WWW allows a Web server to send graphical Web pages of information to a remote client computer system. The remote client computer system then displays the Web pages. Each Web page of the WWW is uniquely identifiable by a Uniform Resource Locator (URL). To view a specific Web page, a client computer system specifies the URL for that Web page in a request (e.g., a HyperText Transfer Protocol (“HTTP”) request). The request is forwarded to the Web server that supports that Web page. When the Web server receives the request, it sends the Web page to the client computer system. When the client computer system receives the Web page, it typically displays the Web page using a browser. A browser is a special-purpose application program that effects the requesting of Web pages and the displaying of Web pages. Commercially available browsers include Microsoft Internet Explorer™ and Netscape Navigator™.
Web pages are typically defined using HyperText Markup Language (“HTML”). HTML provides a standard set of tags that define how a Web page is to be displayed. When a user instructs the browser to display a Web page, the browser sends a request to the Web server to transfer to the client computer system an HTML document that defines the Web page. When the requested HTML document is received by the client computer system, the browser displays the Web page as defined by the HTML document. The HTML document contains various tags that control the displaying of text, graphics, controls, and other features. The HTML document may contain URLs of other Web pages available on that server computer system or other Web servers. Today, thousands of individuals, companies, educational institutions, government agencies and other organizations maintain Web sites which may be accessed and browsed through the use of a Web browser.
Typically, users will access the Internet via telephone lines or high speed data transmission lines hardwired to their computers. However, an expanding area of Internet access is wide-area wireless communications networks. Numerous companies throughout the United States, including Sprint and AT&T, offer their customers wireless Internet access via wireless devices such cellular phones, pagers, personal digital assistants (PDAs), etc.
However, because wireless communications networks have relatively low bandwidths as compared to other types of communications networks, and because most wireless devices have very limited capabilities with respect to the displaying of graphical images, the transmission of graphics-intensive Internet documents in the wireless Internet context has generally proven unsatisfactory in that data transmission is often extremely slow and highly inefficient.
Additionally, in typical prior art systems, Internet documents are transmitted over wireless communications networks to the wireless devices without regard to the type of wireless communications networks to which the wireless devices are connected. Different types of wireless devices will transmit and receive data over different types of wireless communications networks. For example, one popular wireless communications network is the Mobitex network operated by Bell South Wireless Data in the United States. The Mobitex network is a packet data network that uses a proprietary non-IP packet format that must be converted to IP (Internet Protocol) for transmission over IP based networks. In addition, because of the low bandwidth of the Mobitex network, in order to achieve maximum performance, the packets should be paced over the network at an appropriate speed based on the capabilities of the network. By doing so, the waste and performance degradation associated with sending packets too quickly over the network is avoided, reducing both latency and financial loss to the Internet service provider caused by lost packets. Thus, data transmission without regard to wireless communications network type introduces additional delays and inefficiencies.
It is thus clear that there is a need for an improved method of and system for transferring data from the Internet to wireless devices which overcomes the problems associated with the prior art.